Allow zarf to create private-registry secret when a namespace is created

[a1994sc]

Is your feature request related to a problem? Please describe.

When creating a namespace, or when a label is added to a namespace, that the private-registry secret is populated and managed by zarf

Describe the behavior you'd like

• When a namespace resource is created
• Then after the namespace is created zarf creates the secret private-registry

Additional context

• In the file src/internal/packager/helm/post-render.go you already have logic to create the secret on existing namespaces
• Istio creates a configmap, istio-ca-root-cert, whenever a new namespace is created
  • The mutating webhook used by zarf could just always create the secret in all namespaces created after zarf is installed.